This application is based on Patent Application Nos. 2000-111321 filed Apr. 12, 2000 and 2000-326019 filed Oct. 25, 2000 in Japan, the content of which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to a card connector mounted on electronic devices, such as cellular phones, telephones, PDAs (personal digital assistants), portable audio devices and cameras, and more specifically to a connector with a compact structure for reliably preventing an IC card from falling out.
2. Description of the Related Art
In electronic devices such as cellular phones, telephones, PDAs and cameras, a variety of functions are added by inserting an IC card with a built-in CPU or memory IC, such as a SIM (subscriber identity module) card, an MMC (multimedia card), an SD (super density) card, a Memory Stick (tradename) and a Smart Media (tradename) card.
In a connector structure for removably accommodating such an IC card, a plurality of contact terminals connected with a signal processing circuit and a power supply circuit of the electronic device are provided in a connector housing so that they can make contact with a plurality of contact pads formed on the front or back surface of the inserted IC card to electrically connect the IC card to the electronic device on which the connector is mounted.
Many such card connectors have an eject mechanism to remove the inserted card from the connector.
To prevent the card from flying out of the connector during the eject operation or to prevent the card from falling out of the connector due to unexpected external forces during the card insert operation, some card connectors with the eject mechanism of this kind have an appropriate elastic brake piece secured to a predetermined location of the connector housing to apply a contact pressure to the card and thereby produce a frictional force acting in a direction opposite the direction in which the card tends to fall out.
Because the card needs to be taken out of the connector, however, the contact pressure of the brake piece cannot be set unnecessarily large. Hence, with the conventional card fall prevention mechanism based on the contact pressure of the brake piece, it is not possible to reliably prevent the card from falling due to the causes described above or impacts.
In recent years, there are growing demands for reduced size, lower height and reduced weight of the card connector itself, which in turn calls for a compact and lightweight construction for the card fall prevention mechanism.
The present invention has been accomplished under these circumstances and provides a card connector capable of reliably holding an inserted card with a compact mechanism and thereby preventing it from falling out.
Viewed from one aspect the present invention provides a card connector for accepting a card, which has a recess in its side surface and a plurality of contact pads on its bottom surface, and holding it in a connector housing so that the contact pads are in contact with contact terminals arranged in the connector housing, the card connector comprising: an eject mechanism having an eject member, the eject member being adapted to move in a card insertion direction as the card is inserted into the connector and to move in a card eject direction in response to a card eject operation to eject the card; an elastic locking piece having a locking portion to engage in the recess of the card and a stationary portion fixed in the eject member, the elastic locking piece being urged toward the card so that when the elastic locking piece is set free to move elastically by the urging force, the locking portion engages in the recess of the card; and a locking piece guide means for guiding the elastic locking piece to elastically deform it to move the locking portion away from the recess during the card eject operation and, during the card insertion operation, releasing the elastic locking piece from the elastic deformation to engage the locking portion in the recess of the card.
In this invention, the card is formed with the recess for receiving the locking portion, and the elastic locking piece is mounted to the eject member that slides together with the card as the card is inserted or retracted. The elastic locking piece is urged by its own elasticity in a direction that engages the card so that when the elastic locking piece is set free, the locking portion engages in the recess of the card. The motion of the eject member in the card insertion/retraction direction is converted by the locking piece guide means into the motion of the locking portion of the elastic locking piece toward or away from the card so that the locking portion is engaged in the recess during the card insertion and, during the card ejection, is disengaged from the recess.
Because in this invention the locking portion of the elastic locking piece is forcibly moved toward or away from the card not by the movement of the card itself but by the movement of the eject member that behaves in the similar manner to the card, the locking portion of the elastic locking piece can employ a locking structure, such as one shaped like a hook, that can completely block the movement of the card in the retraction direction. This prevents the card from falling out inadvertently or due to unexpected external forces or impacts, thus reliably holding the card at all times during the card insertion.
Further, in the card connector of this invention, because the elastic locking piece is urged in a direction that engages the card so that the elastic locking piece, when set free, causes the locking portion to engage in the recess of the card, the insertion of a second card without the recess makes the locking portion of the elastic locking piece work as a braking piece that presses against the wall surface of the second card to apply to the card a braking force that acts in a direction opposing the card retraction.
Hence, the single card connector of this invention can accept two kinds of cards, one formed with the recess and one without it.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.